Q. 44.5( 6 Votes )
If a genetic disease is transferred from a phenotypically normal but carrier female to only some of the male progeny, the disease is:
A. Autosomal dominant
B. Autosomal recessive
C. Sex-linked dominant
D. Sex-linked recessive
It is a sex-linked recessive disease. If it was an autosomal dominant or recessive disease, then both the male and female progeny should have equal chances of inheriting the disease from parents. But here the disease is transferred from a female carrier to a male progeny specifically, thus it’s sex-linked. In the female carrier the disease is not expressed hence it is sex-linked recessive disease.
For example Haemophilia is a sex-linked recessive disease which shows its transmission from unaffected female carrier to some of the male progeny. The female carriers will be heterozygous.
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